Preparation method of one-dimensional monatomic chain array, monatomic array, single photon source, near-field coupling antenna and implementation method of quantum information storage

Abstract

The disclosure provides a preparation method of a one-dimensional single atom chain array, comprising: cooling and trapping part of target atoms released by an atomic source in a magneto-optical trap by using the magneto-optical trap to form a cold atom group; modulating an initial optical tweezer light beam output by a light beam generation assembly by using a modulation assembly to output a first optical tweezer light beam array; adjusting the position and light power of the first optical tweezer light beam array so that the center of the first optical tweezer light beam array is consistent with the center of the cold atom group, thereby obtaining a single atom array; outputting a second optical tweezer light beam array by using a light path adjusting assembly, so that the first optical tweezer light beam array and the second optical tweezer light beam array form a standing wave optical tweezer array, and the single atom array is converted into a one-dimensional single atom chain array.

Description

TECHNICAL FIELD

[0001] At least one embodiment of the present disclosure relates to the field of optical and quantum information technology, and more particularly to a one-dimensional single atom chain array, a single atom array, a single photon source, a preparation method of near-field coupling antennas, and a realization method of quantum information storage. BACKGROUND

[0002] Neutral atom array is an important research direction in modern quantum physics, and Rydberg atom array is a hot spot in the research of neutral atom array in recent years. Rydberg atoms are neutral atoms excited to high-energy states, and the interaction between them is very strong and controllable. Due to the introduction of Rydberg atoms, the interaction ability between single atoms in the neutral atom array is greatly enhanced, so that the strong interaction between Rydberg atoms in the neutral atom array can be used for the realization and manipulation of quantum bits. Many breakthroughs have made the neutral atom array widely concerned in the fields of quantum network, quantum computing, quantum simulation, quantum precision measurement, etc.

[0003] In a neutral atom-based quantum information system, a light beam is usually focused to a spot with a radius of about 1 μm by using an objective lens with a long working distance and a large numerical aperture. If the frequency of this light beam is slightly less than the transition frequency of the atom (i.e., the frequency is red-shifted), the extremely small spot can form a dipole trap for the atom, which is commonly referred to as an optical tweezer. This dipole trap can be used to trap atoms. When the radius of the dipole trap is less than 4 μm, there is and can only be 0 or 1 atom trapped in the dipole trap. When more atoms are trapped, the atoms in the trap will collide with each other and escape from the trap together. If a spatial light modulator or an acousto-optic deflector is used to divide the light beam into multiple parts and then focus, a dipole trap array arranged by multiple dipole traps can be realized, and a single atom array can be trapped. However, since the process of trapping atoms by the dipole trap is random, the probability of trapping 1 atom in each dipole trap is about = 50%, and it is impossible to trap a single atom deterministically. The probability of trapping a single atom in each dipole trap in the dipole trap array to obtain a defect-free single atom array is , , where N is the number of dipole traps. When = 10, the probability of obtaining a defect-free single atom array is very low.

[0004] Therefore, it is difficult to directly prepare a one-dimensional single atom chain array and a defect-free single atom array in the related art, and it is impossible to trap a single atom deterministically. SUMMARY

[0005] To solve the above and other problems in the prior art, the present disclosure provides a method for preparing a one-dimensional single-atom chain array, which can prepare a one-dimensional single-atom chain array, and the one-dimensional single-atom chain array can prepare a defect-free single-atom array without rearrangement.

[0006] According to a first aspect of the present disclosure, a method for preparing a one-dimensional single-atom chain array is provided, comprising:

[0007] Cooling and trapping part of the target atoms released by the atomic source in the above-mentioned magneto-optical trap by using the magneto-optical trap to form a cold atom group;

[0008] Modulating the initial optical tweezer beam output by the light beam generating assembly by using the modulation assembly to output a first optical tweezer beam array;

[0009] Adjusting the position and optical power of the first optical tweezer beam array to make the center of the first optical tweezer beam array consistent with the center of the cold atom group, thereby obtaining a single-atom array;

[0010] Outputting a second optical tweezer beam array by using the optical path adjusting assembly, the first optical tweezer beam array and the second optical tweezer beam array forming a standing wave optical tweezer array, so that the single-atom array is converted into a one-dimensional single-atom chain array.

[0011] According to an embodiment of the present disclosure, the light beam generating assembly comprises:

[0012] A laser suitable for generating an initial laser beam; and

[0013] A first objective lens suitable for focusing the initial laser beam to output the initial optical tweezer beam,

[0014] Wherein the frequency of the initial laser beam is less than the transition frequency of the target atom.

[0015] According to an embodiment of the present disclosure, the modulation assembly comprises:

[0016] A first half-wave plate suitable for changing the polarization state of the initial optical tweezer beam;

[0017] A spatial light modulator suitable for modulating the initial optical tweezer beam under the control of an externally input modulation signal to output parallel light beams;

[0018] A lens group suitable for focusing the parallel light beams to form convergent light beams; and

[0019] A second objective lens suitable for focusing the convergent light beams to output the first optical tweezer beam array.

[0020] According to an embodiment of the present disclosure, the spatial position of each standing wave optical tweezer in the standing wave optical tweezer array and the spatial distribution of each one-dimensional single atom chain in the one-dimensional single atom chain array are changed by adjusting the angle of the first optical tweezer beam array output by the modulation component.

[0021] According to an embodiment of the present disclosure, the number of single atoms in the one-dimensional single atom chain array is changed by adjusting the power of the first optical tweezer beam array and the second optical tweezer beam array.

[0022] According to an embodiment of the present disclosure, the length and thickness of the one-dimensional single atom chain array are changed by adjusting the numerical aperture of the first objective lens and the second objective lens.

[0023] According to a second aspect of the present disclosure, a preparation method of a single atom array is provided, comprising:

[0024] An atom in each one-dimensional single atom chain in the one-dimensional single atom chain array obtained by the preparation method of the one-dimensional single atom chain array is excited to a Rydberg state by a Rydberg excitation beam;

[0025] Atoms in the one-dimensional single atom chain array in a non-Rydberg state are expelled from a standing wave trap formed by the standing wave optical tweezer array by a resonant beam to prepare a single atom array;

[0026] The resonant beam is a laser beam that resonates with the transition of a target atom from a ground state to an intermediate state.

[0027] According to a third aspect of the present disclosure, a preparation method of a single photon source is provided, comprising:

[0028] Fluorescence emitted by the one-dimensional single atom chain array obtained by the preparation method of the one-dimensional single atom chain array is collected by an optical fiber or a waveguide to form a single photon source array,

[0029] Each one-dimensional single atom chain in the one-dimensional single atom chain array is a single photon source.

[0030] According to a fourth aspect of the present disclosure, a preparation method of a near-field coupling antenna is provided, comprising:

[0031] The single photon source output single atom array optical tweezer beam obtained by the preparation method of the single photon source;

[0032] The single atom array optical tweezer beam is combined with a standing wave optical tweezer array in the preparation method of the one-dimensional single atom chain array;

[0033] adjusting the position and spacing of the single-atom array and the one-dimensional single-atom chain array such that the single-atom array and the one-dimensional single-atom chain array are staggered, and each single atom in the single-atom array is within the Rydberg radius of a superatom formed by each one-dimensional single-atom chain in the one-dimensional single-atom chain array;

[0034] interacting the superatom formed by each one-dimensional single-atom chain with each single atom in the single-atom array one by one to read out the information of the quantum bit in the single-atom array.

[0035] According to a fifth aspect of the present disclosure, a method for implementing quantum information storage is provided, comprising:

[0036] exciting the one-dimensional single-atom chain array obtained by the preparation method of the one-dimensional single-atom chain array into a superatom by using a Rydberg excitation light beam;

[0037] selecting a target atomic energy level in the superatom to form an inverted-pyramid three-level structure;

[0038] using a control light beam that is nearly resonant with the transition frequency from the ground state to the excited state to make the superatom transparent to a probe light beam that is nearly resonant with another transition frequency between the ground state and the excited state, thereby generating an electromagnetically induced effect;

[0039] using the electromagnetically induced effect to transfer quantum information carried by an incident light pulse output by a laser into a long-lived coherent state of the superatom to achieve quantum information storage.

[0040] According to an embodiment of the present disclosure, part of the target atoms released by the atomic source are cooled and trapped in the magneto-optical trap by using the magneto-optical trap to form a cold atom group; then the initial optical tweezer light beam output by the light beam generation assembly is modulated by using the modulation assembly to output a first optical tweezer light beam array; then the position and optical power of the first optical tweezer light beam array are adjusted so that the center of the first optical tweezer light beam array is consistent with the center of the cold atom group, thereby obtaining a single-atom array; finally, a second optical tweezer light beam array is output by using the optical path adjustment assembly, and the first optical tweezer light beam array and the second optical tweezer light beam array form a standing wave optical tweezer array, so that the single-atom array is converted into a one-dimensional single-atom chain array, and a one-dimensional single-atom chain array is successfully prepared, and the one-dimensional single-atom chain array can be used to prepare a defect-free single-atom array without rearrangement. BRIEF DESCRIPTION OF DRAWINGS

[0041] The above and other objects, features and advantages of the present disclosure will become more apparent from the following description of embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0042] Figure 1A flow chart of a preparation method of a one-dimensional monatomic chain array according to an embodiment of the present disclosure is schematically shown;

[0043] Figure 2 A formation schematic diagram of a standing wave atomic optical tweezer in a preparation method of a one-dimensional monatomic chain array according to an embodiment of the present disclosure is schematically shown;

[0044] Figure 3 A working principle diagram of a preparation device of a one-dimensional monatomic chain array according to an embodiment of the present disclosure is schematically shown;

[0045] Figure 4 A flow chart of a preparation method of a monatomic array according to an embodiment of the present disclosure is schematically shown;

[0046] Figure 5 A simple flow schematic diagram of a preparation method of a monatomic array according to an embodiment of the present disclosure is schematically shown;

[0047] Figure 6 A working principle diagram of a preparation device of a single photon source according to an embodiment of the present disclosure is schematically shown;

[0048] Figure 7 A flow chart of a preparation method of a near-field coupling antenna according to an embodiment of the present disclosure is schematically shown;

[0049] Figure 8 A working principle diagram of a preparation device of a near-field coupling antenna according to an embodiment of the present disclosure is schematically shown; and

[0050] Figure 9 A flow chart of an implementation method of quantum information storage according to an embodiment of the present disclosure is schematically shown.

[0051] In the above figures, the meanings of the reference signs are as follows:

[0052] 1-initial optical tweezer beam;

[0053] 2-standing wave atomic optical tweezer;

[0054] 201-potential well depth of the standing wave type dipole trap;

[0055] 3-first objective lens;

[0056] 4-first half-wave plate;

[0057] 5-spatial light modulator;

[0058] 6-first mirror;

[0059] 7-lens group;

[0060] 701-first lens;

[0061] 702 - second lens;

[0062] 703 - second mirror;

[0063] 704 - third mirror;

[0064] 705 - third lens;

[0065] 706 - fourth lens;

[0066] 8 - second objective lens;

[0067] 9 - third objective lens;

[0068] 10 - one-dimensional single atomic chain array;

[0069] 11 - dichroic mirror;

[0070] 12 - fifth lens;

[0071] 13 - fiber array;

[0072] 14 - fourth objective lens;

[0073] 15 - second half wave plate;

[0074] 16 - acousto-optic deflector;

[0075] 17 - beam splitter;

[0076] 18 - alternating one-dimensional single atomic chain and one-dimensional single atomic; DETAILED DESCRIPTION

[0077] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. It should be understood, however, that the description which follows is merely illustrative and is not intended to limit the scope of the present disclosure. In the following detailed description of embodiments of the present disclosure, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present disclosure. However, it would be apparent to one skilled in the art that the embodiments of the present disclosure can be practiced without these specific details. In other instances, well-known structures and functions have not been described in detail in order to avoid obscuring aspects of the present disclosure.

[0078] The terms used herein are merely used to describe specific embodiments and are not intended to limit the present disclosure. The terms "include", "comprise", and the like used herein indicate the presence of the described features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0079] All terms used herein, including technical and scientific terms, have the same meanings as those generally understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having meanings consistent with the context of the present specification, and should not be interpreted in an idealized or excessively formal manner.

[0080] In the case of using expressions like "at least one of A, B, and C", it generally means one or more of the listed items, unless otherwise specified. For example, "at least one of A, B, and C" means A or B or C or any combination thereof.

[0081] A one-dimensional single-atom chain array cannot be prepared in the related art, and a single atom cannot be deterministically trapped.

[0082] Therefore, the present disclosure provides a method for preparing a one-dimensional single-atom chain array. Part of target atoms released by an atom source are cooled and trapped in a magneto-optical trap by using the magneto-optical trap to form a cold atom group. Then, an initial optical tweezer beam output by a beam generation component is modulated by using a modulation component to output a first optical tweezer beam array. The position and optical power of the first optical tweezer beam array are adjusted to keep the center of the first optical tweezer beam array consistent with the center of the cold atom group, so as to obtain a single-atom array. Finally, a second optical tweezer beam array is output by using a light path adjustment component, and the first optical tweezer beam array and the second optical tweezer beam array form a standing wave type optical tweezer array, so that the single-atom array is converted into a one-dimensional single-atom chain array, and the preparation of the one-dimensional single-atom chain array is realized.

[0083] Figure 1 A flowchart of a method for preparing a one-dimensional single-atom chain array according to an embodiment of the present disclosure is schematically shown.

[0084] According to a first aspect of the present disclosure, as Figure 1 shown, the method for preparing a one-dimensional single-atom chain array includes operations S101-S104.

[0085] In operation S101, part of target atoms released by an atom source are cooled and trapped in a magneto-optical trap by using the magneto-optical trap to form a cold atom group.

[0086] In operation S102, an initial optical tweezer beam output by a beam generation component is modulated by using a modulation component to output a first optical tweezer beam array.

[0087] In operation S103, the position and optical power of the first optical tweezer beam array are adjusted to keep the center of the first optical tweezer beam array consistent with the center of the cold atom group, so as to obtain a single-atom array.

[0088] In operation S104, a second optical tweezer beam array is output by using a light path adjustment component, and the first optical tweezer beam array and the second optical tweezer beam array form a standing wave type optical tweezer array, so that the single-atom array is converted into a one-dimensional single-atom chain array.

[0089] According to some embodiments of the present disclosure, part of the target atoms released by the atomic source are cooled and trapped in the magneto-optical trap by using the magneto-optical trap to form a cold atom group; then the initial optical tweezer beam output by the light beam generation assembly is modulated by using the modulation assembly to output a first optical tweezer beam array; then the position and light power of the first optical tweezer beam array are adjusted so that the center of the first optical tweezer beam array is consistent with the center of the cold atom group, thereby obtaining a single atom array; finally, the second optical tweezer beam array is output by using the optical path adjustment assembly, and the first optical tweezer beam array and the second optical tweezer beam array form a standing wave optical tweezer array, so that the single atom array is converted into a one-dimensional single atom chain array, and a one-dimensional single atom chain array is successfully prepared.

[0090] According to some embodiments of the present disclosure, a sealed vacuum system is built using vacuum components, which includes a full-glass vacuum chamber or a metal vacuum chamber composed of multiple glass window pieces, and an ion pump for maintaining the vacuum degree of the vacuum system. The vacuum system also includes an atomic source, such as a rubidium atom dispenser, and then a dry pump, a molecular pump, and an ion pump are used in sequence to raise the vacuum degree in the vacuum system to 10 -9 torr or above, and then the atomic source is turned on to make the target atoms exist in the vacuum chamber.

[0091] According to some embodiments of the present disclosure, in operation S101, the specific steps of cooling and trapping part of the target atoms released by the atomic source in the magneto-optical trap to form a cold atom group include: constructing a light path structure of multiple beams of red-detuned near-resonance light intersecting at an intersection point (i.e., a point in space), such as the most common three pairs of mutually orthogonal counter-propagating beams. Then the center of a pair of anti-Helmholtz coils is adjusted to the intersection point of the red-detuned light beams, so that the center of the magnetic field and the center of the light field coincide to build a magneto-optical trap. The magneto-optical trap can cool and trap part of the target atoms released by the rubidium atom dispenser in the vacuum chamber at the center of the light field and the magnetic field to form a cold atom group.

[0092] According to some embodiments of the present disclosure, the red-detuned light beams refer to the frequencies of the light beams being less than the transition frequency of the atoms.

[0093] According to some embodiments of the present disclosure, the position and optical power of the second optical tweezer beam array are adjusted so that the center of the second optical tweezer beam array is consistent with the center of the cold atom group. The first optical tweezer beam array, the second optical tweezer beam array, and the cold atom group are adjusted to coincide, and the power of the beams of the first optical tweezer beam array and the second optical tweezer beam array is increased so that each optical tweezer beam in the first optical tweezer beam array and the second optical tweezer beam array has a probability of about 50% to grab a single atom from the cold atom group, thereby forming a single atom array. The second optical tweezer beam array interferes with the first optical tweezer beam array to form a standing wave dipole trap, and the single atom array is converted into a one-dimensional single atom chain array by using the standing wave dipole trap, thereby successfully obtaining a one-dimensional single atom chain array.

[0094] According to some embodiments of the present disclosure, the one-dimensional single atom chain array can be used to prepare a defect-free single atom array without rearrangement, and the one-dimensional single atom chain array also has the ability to become an excellent single photon source, a near-field coupling antenna, and can be used as a new type of quantum information storage carrier.

[0095] Figure 2 A standing wave atomic optical tweezer formation diagram in a preparation method of a one-dimensional single atom chain array according to an embodiment of the present disclosure is schematically shown.

[0096] According to some embodiments of the present disclosure, as shown in Figure 2 As shown, an initial laser beam output by a laser is focused into an initial optical tweezer beam 1 with a radius of about 1 μm by using an objective lens with a long working distance and a large numerical aperture, two initial optical tweezer beams 1 are transmitted in opposite directions by a first objective lens 3 and a second objective lens 8 respectively, the frequencies of the two initial optical tweezer beams 1 are far red detuned relative to the atomic transition frequency, the focusing centers of the two initial optical tweezer beams 1 are made to coincide by adjusting the relative positions of the two initial optical tweezer beams 1, and the two initial optical tweezer beams 1 interfere at the focusing center to form a standing wave dipole trap. Figure 2 The potential well depth 201 of the standing wave dipole trap is also shown in the figure, which refers to the energy difference from the bottom to the top of the standing wave dipole trap. Since the initial optical tweezer beam is red detuned, each light intensity maximum in the standing wave dipole trap generated by interference can be regarded as a dipole trap that can grab a single atom. Therefore, the two initial optical tweezer beams 1 will form a standing wave dipole trap, i.e. a standing wave atomic optical tweezer 2, after interference. The multiple light intensity maxima generated by interference enable each standing wave dipole trap to grab a one-dimensional single atom chain. On this basis, the initial optical tweezer beam 1 is expanded to the structure of a standing wave optical tweezer array by using a beam splitting element such as a spatial light modulator.

[0097] According to some embodiments of the present disclosure, when the power of the two initial optical tweezer beams 1 reaches a certain threshold, the standing wave atomic optical tweezer can grab an atom with a probability of 100%.

[0098] According to some embodiments of the present disclosure, the threshold of the power of the two initial optical tweezer beams 1 is 10 mw.

[0099] According to some embodiments of the present disclosure, by adjusting the power of the two initial optical tweezer beams 1, the number of single atoms in each one-dimensional single atom chain can be changed.

[0100] Figure 3 The working principle of the preparation device of the one-dimensional single atom chain array according to some embodiments of the present disclosure is schematically shown.

[0101] According to some embodiments of the present disclosure, the light beam generating assembly comprises a laser and a first objective lens 3. The laser is suitable for generating an initial laser beam; the first objective lens 3 is suitable for focusing the initial laser beam to output an initial optical tweezer beam 1, wherein the frequency of the initial laser beam is less than the transition frequency of the target atom.

[0102] According to some embodiments of the present disclosure, by generating an initial laser beam by means of a laser, focusing the initial laser beam by means of a first objective lens 3 to output an initial optical tweezer beam 1, and the frequency of the initial laser beam being less than the transition frequency of the target atom, the initial optical tweezer beam 1 can form a dipole trap for the target atom, so that the target atom can be trapped.

[0103] According to some embodiments of the present disclosure, as shown in Figure 3 The modulation assembly comprises a first half-wave plate 4, a spatial light modulator 5, a lens group 7, and a second objective lens 8. The first half-wave plate 4 is suitable for changing the polarization state of the initial optical tweezer beam 1; the spatial light modulator 5 is suitable for modulating the initial optical tweezer beam 1 under the control of an externally input modulation signal to output parallel light beams; the lens group 7 is suitable for focusing the parallel light beams to form convergent light beams; and the second objective lens 8 is suitable for focusing the convergent light beams to output a first optical tweezer beam array.

[0104] According to some embodiments of the present disclosure, as shown in Figure 3 The modulation assembly further comprises a first mirror 6, which is suitable for reflecting the initial optical tweezer beam modulated by the spatial light modulator 5 to the lens group 7.

[0105] According to some embodiments of the present disclosure, the spatial light modulator 5 is used to divide one initial optical tweezer beam 1 into a plurality of parallel light beams which are emitted at a certain angle to each other, and the number of the parallel light beams can be arbitrarily changed according to experimental requirements. Then the lens group 7 is used to adjust the parallel light beams to be convergent parallel light beams which are incident to the second objective lens 8 with a large numerical aperture and a long working distance, and the second objective lens 8 focuses the parallel light beams into a first optical tweezer beam array.

[0106] According to some optional embodiments of the present disclosure, the optical path adjusting assembly comprises a first half-wave plate 4, a spatial light modulator 5, a first mirror 6, a lens group 7, and a third objective lens 9. The optical path adjusting assembly modulates the initial optical tweezer beam 1 to output a second optical tweezer beam array, so that the second optical tweezer beam array and the first optical tweezer beam array form a standing wave optical tweezer array, which can realize the preparation of a one-dimensional single atom chain array. The first optical tweezer beam array output by the modulation assembly is adjusted to coincide with the second optical tweezer beam array output by the optical path adjusting assembly, so that the light field at each optical tweezer in the first optical tweezer beam array and the second optical tweezer beam array produces multiple light intensity maxima in the direction of light propagation due to interference, and a standing wave optical tweezer is constructed. Each light intensity maximum in the standing wave optical tweezer can be regarded as a secondary optical tweezer, which can capture a single atom. Therefore, each standing wave optical tweezer can capture a single atom chain. Through this step, the non-deterministic loading single atom array can be converted into a one-dimensional single atom chain array. The number of single atom chains in the array can be changed by adjusting the spatial light modulator, and the number of atoms in each single atom chain can be changed by changing the power of the first optical tweezer beam array and the second optical tweezer beam array.

[0107] According to some optional embodiments of the present disclosure, the optical path adjusting assembly comprises an objective lens and a mirror. The first optical tweezer beam array is recollimated by the objective lens and then reflected by the mirror, and a standing wave optical tweezer can also be constructed.

[0108] According to some optional embodiments of the present disclosure, the optical path adjusting assembly comprises a dichroic mirror and a mirror. The dichroic mirror is designed for 0-degree incident light. The dichroic mirror can be designed to reflect light at the wavelength of the optical tweezer beam and to transmit light at the wavelength of the atom fluorescence. The first optical tweezer beam array is reflected by the dichroic mirror to form a third optical tweezer beam array, so that the first optical tweezer beam array and the third optical tweezer beam array interfere with each other to form a standing wave optical tweezer. Moreover, the fluorescence photons emitted by the atoms in the one-dimensional single atom chain array can pass through the dichroic mirror and be detected by an electron multiplying charge-coupled device (EMCCD) or a complementary metal-oxide-semiconductor (CMOS).

[0109] According to some embodiments of the present disclosure, by adjusting the modulation signal output by the modulation assembly, the angle at which the first optical tweezer beam array is output by the modulation assembly is adjusted, so as to change the spatial position of each standing wave optical tweezer in the standing wave optical tweezer array and change the spatial distribution of each one-dimensional single atom chain in the one-dimensional single atom chain array 10.

[0110] According to some optional embodiments of the present disclosure, the angle at which the modulated parallel light beams are output by the spatial light modulator 5 is adjusted by adjusting the modulation signal output by the spatial light modulator 5, so as to change the spatial position of each standing wave optical tweezer in the array of standing wave optical tweezers, and change the spatial distribution of each one-dimensional single atom chain in the array of one-dimensional single atom chains.

[0111] According to some embodiments of the present disclosure, the spatial distribution of the array of one-dimensional single atom chains 10 includes one-dimensional spatial distribution, two-dimensional spatial distribution, and three-dimensional spatial distribution.

[0112] According to some optional embodiments of the present disclosure, the array of static standing wave dipole trap structures described above can be generated by using optical elements such as spatial light modulators, acousto-optic deflectors, and acousto-optic modulators, so as to obtain an array of static standing wave single atom chains. The spatial distribution of the array of one-dimensional single atom chains can be one-dimensional, two-dimensional, or even three-dimensional, and can be adjusted according to the use requirements.

[0113] According to some embodiments of the present disclosure, by synchronously adjusting the parameters of the optical elements such as spatial light modulators, acousto-optic deflectors, and acousto-optic modulators in two directions, the one-dimensional or two-dimensional movement of the standing wave dipole trap can be realized, and the relative positions of each single atom chain in the array of standing wave single atom chains can be adjusted.

[0114] According to some optional embodiments of the present disclosure, an optical switch is arranged near the standing wave dipole trap, and by controlling the optical switch of the standing wave dipole trap, dynamic switching from the standing wave trap to the traveling wave trap can be realized.

[0115] According to some embodiments of the present disclosure, by adjusting the power of the first optical tweezer beam array and the second optical tweezer beam array, the number of single atoms in the array of one-dimensional single atom chains 10 can be changed.

[0116] According to some embodiments of the present disclosure, by adjusting the numerical aperture size of the first objective lens 3 and the second objective lens 8, the length and thickness of the array of one-dimensional single atom chains 10 can be changed.

[0117] According to some embodiments of the present disclosure, the length and thickness of each single atom chain in the array of one-dimensional single atom chains 10 can be changed by adjusting the numerical aperture of the second objective lens 8. By using this feature, the size of the single atom chain can be controlled within the Rydberg atom blockade radius, so that each single atom chain can be regarded as a Rydberg superatom.

[0118] According to some embodiments of the present disclosure, the superatom formed by the one-dimensional single atom chain can be used for entanglement with other substance bits, and storage of entangled states.

[0119] Figure 4 A flowchart schematically showing a method for preparing an array of single atoms according to an embodiment of the present disclosure is shown.

[0120] According to the second aspect of the present disclosure, Figure 4 As shown, a method for preparing a single atom array is provided, including operations S201 to S202.

[0121] In operation S201 , a Rydberg excitation beam is used to excite an atom in each single-atom chain in the one-dimensional single-atom chain array obtained by the above-mentioned method for preparing the one-dimensional single-atom chain array to a Rydberg state.

[0122] In operation S202 , a resonant light beam is used to expel a plurality of atoms in a non-Rydberg state in a one-dimensional single-atom chain array from a standing wave well formed by a standing wave optical tweezers array, so as to prepare a single-atom array.

[0123] According to some embodiments of the present disclosure, the resonant light beam is a laser beam that generates resonance when a target atom transitions from a ground state to an intermediate state.

[0124] According to some embodiments of the present disclosure, a single-atom array is successfully prepared by using a Rydberg excitation beam to excite one atom in each single-atom chain in the one-dimensional single-atom chain array obtained by the above-mentioned preparation method of the one-dimensional single-atom chain array to a Rydberg state, and then using a resonant beam to expel multiple atoms in the one-dimensional single-atom chain array that are in a non-Rydberg state from a standing wave well formed by a standing wave optical tweezers array.

[0125] Figure 5 A simple flow chart of a method for preparing a single atom array according to an embodiment of the present disclosure is schematically shown.

[0126] According to some embodiments of the present disclosure, Figure 5 As shown, after trapping multiple atoms using a one-dimensional single-atom chain array, a Rydberg excitation beam is used to excite one of these atoms into a Rydberg state. Due to the Rydberg blockade effect, only one atom within the Rydberg radius is excited into the Rydberg state. A resonant beam resonating with the atomic ground-to-intermediate-state transition is then used to heat and expel atoms from the potential well, thereby achieving deterministic preparation of single atoms in a standing wave trap. One of the beams in the standing wave dipole trap, namely the first or second optical tweezers beam array, is then turned off. After turning off one of the beams in the standing wave dipole trap, the standing wave dipole trap is switched to a traveling wave trap, completing the preparation of a single-atom array in the traveling wave trap array.

[0127] According to some embodiments of the present disclosure, the efficiency of the Rydberg excitation process is M times that of a single atom, where M is the number of captured atoms, that is, the number of atoms in a single atom chain. Therefore, each single atom chain can be regarded as a Rydberg superatom.

[0128] According to some embodiments of the present disclosure, the one-dimensional single-atom chain array is suitable for developing high-performance optical sensors. The single-atom chain can be used as a superatom, and due to the optical collective effect of the superatom, it exhibits extremely high sensitivity to environmental changes (such as temperature, magnetic field, etc.), and a high-performance optical sensor can be developed.

[0129] According to some embodiments of the present disclosure, the spacing between the two adjacent single atoms in the one-dimensional single-atom chain is an integer multiple of the half wavelength of the optical tweezers beam (the first optical tweezers beam). The one-dimensional single-atom chain with this feature has a special collective effect: the total spontaneous emission direction of the fluorescent photons of these atoms arranged in a line is not completely random, and a considerable part of the fluorescent photons is emitted in the direction of the one-dimensional single-atom chain. The intensity of this directional fluorescent signal is much higher than that of the fluorescent signal emitted by multiple independent single atoms, and can be made into a high-intensity single-photon source. And due to the homogeneity of the single atoms, the single-photon source made has very excellent homogeneity of the single photons emitted.

[0130] According to a third aspect of the present disclosure, a preparation method of a single-photon source is provided, which comprises collecting the fluorescence emitted by the one-dimensional single-atom chain array obtained by the preparation method of the one-dimensional single-atom chain array described above by using an optical fiber or a waveguide to form a single-photon source array.

[0131] According to some embodiments of the present disclosure, each one-dimensional single-atom chain in the one-dimensional single-atom chain array is a single-photon source.

[0132] According to some embodiments of the present disclosure, by collecting the fluorescence emitted by the one-dimensional single-atom chain array obtained by the preparation method of the one-dimensional single-atom chain array described above by using an optical fiber or a waveguide, a single-photon source array can be formed, and the intensity of the single-photon source is higher.

[0133] Figure 6 The working principle diagram of the preparation device of the single-photon source according to the embodiments of the present disclosure is schematically shown.

[0134] According to some embodiments of the present disclosure, as Figure 6As shown, the preparation device of the single photon source includes: a first objective lens 3, a first half-wave plate 4, a spatial light modulator 5, a first mirror 6, a lens group 7, a second objective lens 8, a third objective lens 9, a dichroic mirror 11, a fifth lens 12, and a fiber array 13. After the initial tweezer light beam 1 passes through the first objective lens 3, the first half-wave plate 4, the spatial light modulator 5, the first mirror 6, the lens group 7, and the second objective lens 8, a first light tweezer beam array is formed. On the basis of obtaining the one-dimensional single atom chain array by using the preparation method of the one-dimensional single atom chain array, the fourth lens 706, the third lens 705, the third mirror 704, the dichroic mirror 11, the fifth lens 12, and the fiber array 13 are arranged in the optical path structure where the third objective lens 9 is located, and the fluorescence emitted by the one-dimensional single atom chain is collected into the fiber array 13, so as to form a single photon source array, and each fiber in the fiber array 13 is a single photon source and corresponds to each chain in the one-dimensional single atom chain array.

[0135] According to some optional embodiments of the present disclosure, the fiber array 13 can be replaced by a waveguide array.

[0136] According to some embodiments of the present disclosure, the fluorescence emitted by the single atom chain can be coupled into the fiber array 13 or the waveguide array by adjusting the position of the fiber array or the waveguide array. After this step is completed, the fiber array or the waveguide array can collect the fluorescence of the atoms in the one-dimensional single atom chain array, and form a high-intensity single photon source.

[0137] According to some embodiments of the present disclosure, the directional radiation of the one-dimensional single atom chain obtained by using the standing wave type dipole trap can form a single photon source, and the directional radiation of the array composed of the standing wave single atom chains can also form a single photon source array.

[0138] Figure 7 A flowchart of a preparation method of a near-field coupling antenna according to an embodiment of the present disclosure is schematically shown.

[0139] According to a fourth aspect of the present disclosure, as Figure 7 A preparation method of a near-field coupling antenna is provided, which includes operations S301-S304.

[0140] In operation S301, a single atom array tweezer light beam is output by using the single photon source obtained by the preparation method of the single photon source.

[0141] In operation S302, the single atom array tweezer light beam is combined with the standing wave type tweezer array in the preparation method of the one-dimensional single atom chain array.

[0142] In operation S303, the positions and intervals of the single-atom array and the one-dimensional single-atom chain array are adjusted so that the single-atom array and the one-dimensional single-atom chain array are staggered, and each single atom in the single-atom array is within the Rydberg radius of the superatom formed by each one-dimensional single-atom chain in the one-dimensional single-atom chain array.

[0143] In operation S304, the superatom formed by each one-dimensional single-atom chain interacts with each single atom in the single-atom array one by one to read out the information of the quantum bit in the single-atom array.

[0144] According to some embodiments of the present disclosure, a single-atom array optical tweezers beam is output by using a single-photon source obtained by the preparation method of the single-photon source described above; the single-atom array optical tweezers beam is combined with the standing wave optical tweezers array in the preparation method of the one-dimensional single-atom chain array described above; the positions and intervals of the single-atom array and the one-dimensional single-atom chain array are adjusted so that the single-atom array and the one-dimensional single-atom chain array are staggered, and each single atom in the single-atom array is within the Rydberg radius of the superatom formed by each one-dimensional single-atom chain in the one-dimensional single-atom chain array; the superatom formed by each one-dimensional single-atom chain interacts with each single atom in the single-atom array one by one, thereby assisting in reading out the quantum bit information of the single atom in the single-atom array; and the photons emitted by the one-dimensional single-atom chain are detected to obtain the information of the one-dimensional single-atom chain as an auxiliary quantum bit, thereby indirectly obtaining the quantum bit information of the single atom in the single-atom array.

[0145] According to some embodiments of the present disclosure, the near-field coupling antenna can be used for coupling of the single-atom chain with other substance bits (such as atoms, ions, quantum dots, quasi-atoms) to read out the state of the quantum bit.

[0146] According to some embodiments of the present disclosure, the one-dimensional single-atom chain is composed of atoms, which can interact with any substance that can interact with atoms, such as a superatom as an auxiliary quantum bit. When the superatom composed of the one-dimensional single-atom chain interacts with a quantum bit atom, the interaction strength and the detectable fluorescence intensity are both stronger than those of a single atom. If the one-dimensional single-atom chain is used as an auxiliary bit to read out the state of the quantum bit, the state readout efficiency of the quantum system can be improved. This advantage makes the one-dimensional single-atom chain available as a high-efficiency near-field coupling antenna.

[0147] Figure 8 The working principle diagram of the preparation device of the near-field coupling antenna according to the embodiments of the present disclosure is schematically shown.

[0148] According to some embodiments of the present disclosure, as Figure 8As shown, the preparation device of the near-field coupling antenna includes a first objective lens 3, a first half-wave plate 4, a spatial light modulator 5, a first mirror 6, a lens group 7, a second objective lens 8, a third objective lens 9, a dichroic mirror 11, a fifth lens 12, a fiber array 13, a fourth objective lens 14, a second half-wave plate 15, an acousto-optic deflector 16, and a beam splitter 17. The optical path structure of the preparation device of the near-field coupling antenna adds the fourth objective lens 14, the second half-wave plate 15, the acousto-optic deflector 16, and the beam splitter 17 on the basis of the optical path structure of the single-photon source preparation device, and constructs an experimental optical path of a single-atom array, so that a single-atom array tweezer beam and an atomic chain tweezer beam are combined. After the single-atom array tweezer beam and the atomic chain array tweezer beam are combined, the positions and intervals of the arrays formed by the two kinds of tweezer beams are adjusted, so that the single-atom array and the atomic chain array are staggered, and each single atom in the single-atom array is within the Rydberg radius of the superatom formed by the atomic chain. Each Rydberg superatom formed by the single-atom chain can interact with each single atom in the single-atom array as a quantum bit one by one as an auxiliary bit. After the interaction, the single-atom chain can directionally radiate photons containing quantum bit information at high intensity. Reading the information in these photons can obtain the state of the quantum bit.

[0149] According to some embodiments of the present disclosure, the experimental optical path constructed including the fourth objective lens 14, the second half-wave plate 15, the acousto-optic deflector 16, and the beam splitter 17 further includes a spatial light modulator, an acousto-optic deflector, a spatial light modulator, and an acousto-optic deflector to control the position of each tweezer in the single-atom array, and complete the rearrangement of the defect-free single-atom array.

[0150] Figure 9 A flowchart of an implementation method of quantum information storage according to an embodiment of the present disclosure is schematically shown.

[0151] According to a fifth aspect of the present disclosure, as Figure 9 As shown, an implementation method of quantum information storage is provided, including operations S401 to operation S404.

[0152] In operation S401, a one-dimensional single-atom chain array obtained by the preparation method of the one-dimensional single-atom chain array is excited into a superatom by a Rydberg excitation beam.

[0153] In operation S402, a target atomic energy level is selected in the superatom to form an inverted pyramid type three-level structure.

[0154] In operation S403, a control laser beam with a transition frequency near resonance between a ground state and an excited state is used to make the superatom transparent to a probe beam with a transition frequency near resonance with another ground state and excited state, and to produce an electromagnetic induction effect.

[0155] In operation S404 , quantum information carried by an incident light pulse output by a laser is transferred to a long-lived coherent state of a meta-atom by utilizing an electromagnetic induction effect, so as to realize quantum information storage.

[0156] According to some embodiments of the present disclosure, a one-dimensional single-atom chain array obtained by the above-mentioned preparation method of the one-dimensional single-atom chain array is excited into a super-atom by using a Rydberg excitation beam; a target atomic energy level is selected in the super-atom to form an inverted pyramid-shaped three-level energy structure; a regulated laser beam that is nearly resonant with the transition frequency from the ground state to the excited state is used to make the super-atom transparent to a detection beam that is nearly resonant with another ground state and excited state transition frequency, thereby generating an electromagnetic induction effect; and the electromagnetic induction effect is used to transfer the quantum information carried by the incident light pulse output by the laser to the long-lived coherent state of the super-atom, thereby realizing the storage of quantum information.

[0157] According to some embodiments of the present disclosure, after a one-dimensional single-atom chain is excited to become a superatom, appropriate atomic energy levels are selected within the superatom to form an inverted pyramid (Λ)-type three-level structure. This structure has two stable ground states and one excited state. A strong laser beam that is nearly resonant with the transition frequency of one ground state and excited state is then used as control light to make the superatom transparent to the probe light that is nearly resonant with the transition frequency of another ground state and excited state, thereby generating an electromagnetic induction effect. Utilizing the electromagnetic induction effect, the speed of the incident light pulse carrying quantum information can be slowed down or even completely stopped, transferring its information to the long-lived coherent state of the superatom. The strong collective effect of the superatom helps to enhance the efficiency and fidelity of information storage and reduce coherence loss. When information needs to be read, the stored light pulse can be re-extracted from the superatom by adjusting the parameters of the control light, thereby enabling information reading and transmission.

[0158] Those skilled in the art will appreciate that the features described in the various embodiments and / or claims of this disclosure may be combined and / or coupled in various ways, even if such combinations and / or couplings are not explicitly described in this disclosure. In particular, the features described in the various embodiments and / or claims of this disclosure may be combined and / or coupled in various ways without departing from the spirit and teachings of this disclosure. All such combinations and / or couplings are intended to fall within the scope of this disclosure.

[0159] The embodiments of the present disclosure are described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present disclosure. Although each embodiment has been described separately above, this does not mean that the measures in each embodiment cannot be used in combination to advantage. The scope of the present disclosure is defined by the appended claims and their equivalents. Without departing from the scope of the present disclosure, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A method for preparing a one-dimensional single atom chain array, comprising: cooling and trapping part of target atoms released from an atom source in a magneto-optical trap by the magneto-optical trap to form a cold atom group; modulating an initial optical tweezer beam output by a beam generation component by a modulation component to output a first optical tweezer beam array; adjusting the position and optical power of the first optical tweezer beam array to keep the center of the first optical tweezer beam array consistent with the center of the cold atom group to obtain a single atom array; outputting a second optical tweezer beam array by a light path adjustment component, the first optical tweezer beam array and the second optical tweezer beam array forming a standing wave optical tweezer array, so that the single atom array is converted into a one-dimensional single atom chain array; wherein the angle at which the first optical tweezer beam array is output by the modulation component is modulated by adjusting the modulation signal output by the modulation component, so as to change the spatial position of each standing wave optical tweezer in the standing wave optical tweezer array, and change the spatial distribution of each one-dimensional single atom chain in the one-dimensional single atom chain array; the number of single atoms in the one-dimensional single atom chain array is changed by adjusting the power of the first optical tweezer beam array and the second optical tweezer beam array.

2. The method of claim 1, wherein the one-dimensional monatomic chain array is prepared by the steps of: The beam generation component comprises: a laser suitable for generating an initial laser beam; and a first objective lens suitable for focusing the initial laser beam to output the initial optical tweezer beam, wherein the frequency of the initial laser beam is less than the transition frequency of the target atom.

3. The method of claim 2, wherein the one-dimensional array of monatomic chains is prepared by, The modulation component comprises: a first half-wave plate suitable for changing the polarization state of the initial optical tweezer beam; a spatial light modulator suitable for modulating the initial optical tweezer beam under the control of an externally input modulation signal to output parallel beams; a lens group suitable for focusing the parallel beams to form convergent beams; and a second objective lens suitable for focusing the convergent beams to output the first optical tweezer beam array.

4. The method of claim 3, wherein the one-dimensional array of monatomic chains is prepared by, The length and thickness of the one-dimensional single atom chain array are changed by adjusting the numerical aperture size of the first objective lens and the second objective lens. 5.A method for preparing a single atom array, comprising: exciting one atom in each single atom chain of a one-dimensional single atom chain array obtained by the method for preparing a one-dimensional single atom chain array according to any one of claims 1-4 to a Rydberg state by a Rydberg excitation beam; evacuating a plurality of atoms in the one-dimensional single atom chain array in a non-Rydberg state from a standing wave trap formed by the standing wave optical tweezer array by a resonant beam to prepare a single atom array; wherein the resonant beam is a laser beam resonant with the transition of the target atom from a ground state to an intermediate state. 6.A method for preparing a single photon source, comprising: collecting fluorescence emitted by a one-dimensional single atom chain array obtained by the method for preparing a one-dimensional single atom chain array according to any one of claims 1-4 by an optical fiber or a waveguide to form a single photon source array, wherein each one-dimensional single atom chain in the one-dimensional single atom chain array is a single photon source. 7.A method for preparing a near-field coupling antenna, comprising: outputting a single atom array optical tweezer beam by a single photon source obtained by the method for preparing a single photon source according to claim 6; combining the single-atom array optical tweezer beam with the standing wave optical tweezer array in the preparation method of the one-dimensional single-atom chain array according to any one of claims 1-4; adjusting the position and spacing of the single-atom array and the one-dimensional single-atom chain array, so that the single-atom array and the one-dimensional single-atom chain array are staggered, and each single atom in the single-atom array is within the Rydberg radius of the superatom formed by each one-dimensional single-atom chain in the one-dimensional single-atom chain array; interacting each superatom formed by each one-dimensional single-atom chain with multiple single atoms in the single-atom array one by one to read out the information of the quantum bits in the single-atom array.

8. A method for implementing quantum information storage, comprising: exciting the one-dimensional single-atom chain array obtained by the preparation method of the one-dimensional single-atom chain array according to any one of claims 1-4 into a superatom by using a Rydberg excitation light beam; selecting a target atomic energy level in the superatom to form an inverted pyramid three-level structure; using a control laser beam that is nearly resonant with the transition frequency from the ground state to the excited state to make the superatom transparent to a probe light beam that is nearly resonant with another ground state and excited state transition frequency, generating an electromagnetic induction effect; using the electromagnetic induction effect to transfer quantum information carried by an incident light pulse output by a laser into a long-lived coherent state of the superatom to achieve quantum information storage.

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